Inter-channel phase difference parameter encoding method and apparatus

Patent metadata

Field	Value
Publication number	US-11031021-B2
Application number	US-201916723449-A
Country	US
Kind code	B2
Filing date	Dec 20, 2019
Priority date	Jun 30, 2017
Publication date	Jun 8, 2021
Grant date	Jun 8, 2021

Abstract

This application discloses an IPD parameter encoding method, including: obtaining a reference parameter used to determine an IPD parameter encoding scheme of a current frame of a multi-channel signal; determining the IPD parameter encoding scheme of the current frame based on the reference parameter, where the determined IPD parameter encoding scheme of the current frame is one of at least two preset IPD parameter encoding schemes; and processing an IPD parameter of the current frame based on the determined IPD parameter encoding scheme of the current frame. The technical solutions provided in this application can improve encoding quality of the multi-channel signal.

First claim

What is claimed is:

1. An inter-channel phase difference parameter encoding method, comprising:
obtaining a reference parameter used to determine an inter-channel phase difference (IPD) parameter encoding scheme of a current frame of a multi-channel signal;
determining the IPD parameter encoding scheme of the current frame based on the reference parameter, wherein the determined IPD parameter encoding scheme of the current frame is one of at least two preset IPD parameter encoding schemes; and
processing an IPD parameter of the current frame based on the determined IPD parameter encoding scheme of the current frame;
wherein the reference parameter comprises a signal characteristic parameter of the current frame and signal characteristic parameters of A frames prior to the current frame, wherein A is an integer not less than 1;
the signal characteristic parameter of the current frame comprises a parameter indicating correlation between a left channel and a right channel of the current frame; and
the signal characteristic parameters of the A frames prior to the current frame comprise an IPD parameter encoding scheme of each of the A frames and a signal type of each of the A frames, wherein
the signal type comprises a voice type or a music type.

2. The method according to claim 1 , wherein the reference parameter comprises the parameter indicating the correlation between the left channel and right channel of the current frame; and
if a value of the parameter indicating the correlation between the left channel and right channel of the current frame is greater than or equal to a first threshold, the IPD parameter encoding scheme of the current frame is a first encoding scheme in the at least two IPD parameter encoding schemes.

3. The method according to claim 2 , wherein the first threshold is 0.75.

4. The method according to claim 2 , wherein the first encoding scheme comprises any one of the following manners:
a group IPD parameter encoding scheme;
skipping encoding an IPD parameter; or
setting a value of an IPD parameter to 0.

5. The method according to claim 2 , wherein if the IPD parameter encoding scheme of the current frame is not the first encoding scheme, the IPD parameter encoding scheme of the current frame is a second encoding scheme, wherein
the second encoding scheme comprises an IPD parameter encoding scheme of a subband set, or a subband IPD parameter encoding scheme, and the subband IPD parameter encoding scheme is encoding subband IPD parameters of some or all of subbands of the current frame.

6. The method according to claim 5 , wherein the second encoding scheme is the subband IPD parameter encoding scheme; and
the processing an IPD parameter of the current frame based on the determined IPD parameter encoding scheme of the current frame comprises:
calculating IPD parameters of all or some of subbands of a left channel frequency domain signal and a right channel frequency domain signal of the current frame; and
encoding the IPD parameters that are of all or some of the subbands and that are obtained through calculation.

7. The method according to claim 2 , wherein the reference parameter comprises the IPD parameter encoding scheme of each of the A frames and the signal type of each of the A frames; and
if the IPD parameter encoding scheme of each of the A frames is the first encoding scheme in the at least two IPD parameter encoding schemes, and the signal type of each of the A frames is a music type, the IPD parameter encoding scheme of the current frame is the first encoding scheme.

8. The method according to claim 1 , wherein before processing an IPD parameter of the current frame based on the determined IPD parameter encoding scheme of the current frame, the method further comprises:
determining whether the determined IPD parameter encoding scheme of the current frame needs to be adjusted;
adjusting the determined IPD parameter encoding scheme of the current frame when it is determined that the determined IPD parameter encoding scheme of the current frame needs to be adjusted; and
the processing an IPD parameter of the current frame based on the determined IPD parameter encoding scheme of the current frame comprises:
processing the IPD parameter of the current frame based on the adjusted IPD parameter encoding scheme of the current frame.

9. The method according to claim 8 , wherein the determining whether the determined IPD parameter encoding scheme of the current frame needs to be adjusted is performed based on IPD parameter encoding schemes of the A frames prior to the current frame.

10. The method according to claim 1 , wherein the parameter indicating the correlation between the left channel and right channel of the current frame is obtained by using the following calculation formula:

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Assignees

• Huawei Tech Co Ltd

Inventors

• Zhang Xingtao
• Li Haiting
• Liu Zexin
• Miao Lei

Classifications

• G10L19/008 Primary

  Multichannel audio signal coding or decoding using interchannel correlation to reduce redundancy, e.g. joint-stereo, intensity-coding or matrixing · CPC title

• H04S2420/03

  Application of parametric coding in stereophonic audio systems · CPC title

• G10L19/032

  Quantisation or dequantisation of spectral components · CPC title

• H04S2400/03

  Aspects of down-mixing multi-channel audio to configurations with lower numbers of playback channels, e.g. 7.1 -> 5.1 (H04S2400/01 takes precedence) · CPC title

• H04S3/008

  in which the audio signals are in digital form, i.e. employing more than two discrete digital channels (data reduction aspects thereof based on psychoacoustics G10L19/02) · CPC title